Volume 16, No. 12, December 2016, Pages 3114-3129 PDF(1.46 MB)
Chemical Characterization and Source Apportionment of PM2.5 in Rabigh, Saudi Arabia
Shedrack R. Nayebare1,2, Omar S. Aburizaiza3, Haider A. Khwaja1,2, Azhar Siddique4, Mirza M. Hussain1,2, Jahan Zeb2, Fida Khatib3, David O. Carpenter5, Donald R. Blake6
1 Department of Environ. Health Sciences, School of Public Health, University at Albany, Albany, NY 12201, USA
2 Wadsworth Center, New York State Department of Health, Albany, NY 12201, USA
3 Unit for Ain Zubaida Rehabilitation & Ground Water Research, King Abdulaziz University, Jeddah, Saudi Arabia
4 Qatar Environment and Energy Research Institute, Hamad Bin Khalifa University, Qatar Foundation, Doha, Qatar
5 Institute for the Health and the Environment, University at Albany, 5 University Place, Rensselaer, NY 12144, USA
6 Department of Chemistry, University of California, Irvine, CA 92617, USA
- First study to assess fine particulate air pollution in Rabigh, Saudi Arabia.
- A detailed source apportionment and chemical characterization of PM2.5 presented.
- PM2.5 sources include fossil fuels, sea sprays, industrial and vehicular emissions.
The present study describes the measurement, chemical characterization and delineation of sources of fine particulate matter (PM2.5) in Rabigh, Saudi Arabia. The 24-h PM2.5 was collected from May 6th–June 17th, 2013. The sources of various air pollutants and their characterization was carried by computations of Enrichment Factor (EF), Positive Matrix Factorization (PMF) and Backward-in-time Trajectories. The 24-h PM2.5 showed significant temporal variability with average (37 ± 16.2 µg m–3) exceeding the WHO guideline (20 µg m–3) by 2 fold. SO42–, NO3–, NH4+ and Cl– ions dominated the ionic components. Two broad categories of aerosol Trace Elements (TEs) sources were defined as anthropogenic (Ni, V, Zn, Pb, S, Lu and Br) and soil/crustal derived (Si, Rb, Ti, Fe, Mn, Mg, K, Sr, Cr, Ca, Cu, Na and Al) elements from computations of EF. Anthropogenic elements originated primarily from fossil-fuel combustion, automobile and industrial emissions. A factor analysis model (PMF) indicated the major sources of PM2.5 as Soil (Si, Al, Ti, Fe, Mg, K and Ca); Industrial Dust (Ca, Fe, Al, and Si); Fossil-Fuel combustion (V, Ni, Pb, Lu, Cu, Zn, NH4+, SO42– and BC); Vehicular Emissions (NO3–, C2O42–, V and BC) and Sea Sprays (Cl– and Na). Backward-in-time trajectories showed a significant contribution by long distance transport of fine aerosols to the overall daily PM2.5 levels. Results are consistent with previous studies and highlight the need for more comprehensive research into particulate air pollution in Rabigh and the neighboring areas. This is essential for the formulation of sustainable guidelines on air pollutant emissions in Saudi Arabia and the whole Middle East.
Black carbon; Trace elements; Enrichment factor; PMF; PM2.5 mass reconstruction.